Rock-drilling machine



Unire-n stares earner carica.

IN'GEBRET BHN, OF SRUMSAND, NORWAY.

ROCK-DRTLLING- MACHINE.

Specication of Letters Patent.

Patented Feb. 22, 1921.

Application led May 20, 1919. Serial No. 298,514.

To all 'whom 'z may concern.'

Be it known that I, INGnnn'r BHN, a subject of the King of Norway, residing at Srumsand, Norway, have invented certain new and useful Improvements in Rock- Drilling Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art` to which itV According to the present invention the rock drills receive their reciprocating movenient from the rotating crank at the front end of a central shaft.

form of the invention is diagrammatically illustrated by an axial section on the drawing. Y

Y The machine is driven from the electric motor 16 if'necessary by means of gears or the like. Shaft 9 is provided with a crank 'v bearing 8 and a crank disk 7 carrying a crankpin 6. TheI crank pin 6 is connected by means of rods 5 to T-levers 4, which are pivoted at their apex on a disk 12 and are given an oscillating movement by means of the crank pin 6. There is suiicient looseness in the joints of the pivotal connection` of the rods 5 to permit slight lateral movement thereof. By the oscillations of the T-levers 4 the rock drills 1, which are connected to the free ends of the T-levers, are given a reciprocating movement. Links 2 pivoted at the front end of projecting arms 8 serve to guide the rock drills in their movement, and an annular sleeve or projecting flange 13 serves to protect the mechanism against falling rocks or the like.-A The' front disk 12 is fastened to a cylinder or drum 10, which is journaled in sleeve 11 mounted on the machine frame, and the said cylinder or drum 10 is given a slow` rotating movement from motor 16 by means of gears 14, l5.

The operation of the machine is exactly similar to the operation of the machine described in applicants above named application, the feeding movement'taking place by driving the carrying wheels from the motor 16.

Claim--` In a rock drilling machine, a plurality of reciprocating drills, a central rotary shaft, a crank at the front end of the latter, a plurality of pivoted T-levers loosely articulated to said crank, and means connecting the free ends of the T-levers to the drills whereby theV latter are reciprocated.

In testimony that I claim the foregoing as my invention, I have signed my name in presence cf twol subscribing witnesses.

INGEBRET'BHN.

Witnesses:

A. I-IEDENCHON,4 MARGARET BUGGE. 

